The results of TH3::Project3DProfile() are not meaningful.
I believe I found the faulty line in this member function:
TProfile2D TH3::DoProjectProfile2D(const char name, const char * title, TAxis* projX, TAxis* projY,
bool originalRange, bool useUF, bool useOF)
p2->Fill( projY->GetBinCenter(iybin) , projX->GetBinCenter(ixbin), outAxis->GetBinCenter(outbin), cont);
Could it be that this line should read:
p2->Fill( projY->GetBinCenter(iybin) , projX->GetBinCenter(ixbin), cont);
I am currently using Root 5.34/18, but this feature has occurred in previous versions as well. I would appreciate if this could be fixed in the next version.